Two fat black arrows are swimming along together, when they see a single skinny black arrow coming toward them. They are afraid of strangers, and they know that the skinny one must be mean and tough if it's not afraid to travel alone. So they turn to the side and get out of the skinny arrow's way.
BECAUSE AN OBJECTS DENSITY SHOWS HOW MUCH WEIGHT IS PER CUBIC UNIT. LIKE SAD HAS MORE DENSITY THAN WATER SO IT SINKS WHILE WOOD HAS LESS DENSITY THAN WATER SO IT FLOATS